Volume 205, 2017

Quantitative SERS by hot spot normalization – surface enhanced Rayleigh band intensity as an alternative evaluation parameter for SERS substrate performance

Abstract

The performance of surface-enhanced Raman spectroscopy (SERS) substrates is typically evaluated by calculating an enhancement factor (EF). However, it is challenging to accurately calculate EF values since the calculation often requires the use of model analytes and requires assumptions about the number of analyte molecules within the laser excitation volume. Furthermore, the measured EF values are target analyte dependent and thus it is challenging to compare substrates with EF values obtained using different analytes. In this study, we propose an alternative evaluation parameter for SERS substrate performance that is based on the intensity of the surface plasmon enhanced Rayleigh band (IRayleigh) that originates from the amplified spontaneous emission (ASE) of the laser. Compared to the EF, IRayleigh reflects the enhancing capability of the substrate itself, is easy to measure without the use of any analytes, and is universally applicable for the comparison of SERS substrates. Six SERS substrates with different states (solid, suspended in liquid, and hydrogel), different plasmonic nanoparticle identities (silver and gold), as well as different nanoparticle sizes and shapes were used to support our hypothesis. The results show that there are excellent correlations between the measured SERS intensities and IRayleigh as well as between the SERS homogeneity and the variation of IRayleigh acquired with the six SERS substrates. These results suggest that IRayleigh can be used as an evaluation parameter for both SERS substrate efficiency and reproducibility.

Associated articles

Supplementary files

Article information

Article type
Paper
Submitted
10 4 2017
Accepted
21 6 2017
First published
19 9 2017

Faraday Discuss., 2017,205, 491-504

Quantitative SERS by hot spot normalization – surface enhanced Rayleigh band intensity as an alternative evaluation parameter for SERS substrate performance

H. Wei, A. McCarthy, J. Song, W. Zhou and P. J. Vikesland, Faraday Discuss., 2017, 205, 491 DOI: 10.1039/C7FD00125H

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements